Field of Invention
The present invention relates to the field of pharmaceutics, cosmetics and dietetics and has for objective to make pure carrageenan films for the manufacturing of hard and soft capsules or gelled capsules as well as a method for making the said film and soft capsules.
Discussion of the Background
Currently, the shell of both gelled capsules and capsules comprises gelatin as a base used either pure (for gelled capsules) or in combination with different substances, glycerine, sorbitol, etc, in the case of soft capsules.
However, due to major problems arising from the origin of gelatin, which comes mainly from bovine bones, the disease called "mad cow disease" or BSE (Bovin Spongiform Encephalitis) makes it crucial to find a substitute for such product.
Quite a number of products having gelifying characteristics or forming pseudo-colloidal solutions have been tested such as starch, cellulose, and hydrocolloids such as alginate, pectin, xanthane gum, etc.
The results obtained have not been conclusive in the case of hard and soft capsules, apart from the cellulosic by-products such as hydroxypropylmethyl cellulose for the manufacturing of gelled capsules.
Quite an amount of work has been carried out and has led to patents. Among these, the Japanese patents No. 09025228, No. 62289530, No. 61010508 and U.S. Pat. Nos. 5,342,626 mention carrageenans as a substitute for gelatin. But, in every case, they are always combined with another gelling agent such as mannans, galactomannans, agar, etc, and in fairly low concentrations in the order of 1 to 2%. The U.S. Pat. No. 5,342,626 and Japanese patent No 60012943 only mention Kappa carrageenans (K-carrageenans) even though it is known that films obtained from this type of carrageenans present an important power of retraction: synerese phenomenon working against the manufacturing of hard and soft capsules. Furthermore, this type of carrageenans does not enable to obtain a highly concentrated fluid solution in hot work as in cold work.